Oh, so that's how Gaussian Splats achieve view-dependence. Strongly reminds me of work on realtime relighting from a decade ago. IIRC some version of Halo used

Oh, so that's how Gaussian Splats achieve view-dependence. Strongly reminds me of work on realtime relighting from a decade ago. IIRC some version of Halo used a couple of SH coefficients (either per pixel or per vertex) for some dynamic shadow / lighting thing. Then, it devolved into figuring out a better set of decomposition functions (SH is Fourier Transform over a spherical coordinate basis). IIRC Haar wavelets worked well too. I'd guess that with modern approaches, a learned function would do even better.